Digital Piano Glossary — Plain-English Definitions

Buying a digital piano means navigating a maze of technical terms. This glossary defines the concepts you'll meet on spec sheets and in reviews, written in plain language for people choosing their first — or next — piano.

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Keys & Action Sound & Voicing Pedals Connectivity Features & Performance

Keys & Action

Weighted keys: Keys that resist finger pressure the way acoustic piano keys do. Essential for building piano technique. Digital pianos achieve this by adding small weights or a hammer mechanism under each key.
Graded hammer action: Weighted keys where the bass end is heavier than the treble — the same gradient you feel on an acoustic grand. This is the standard for any piano meant for serious practice.
Semi-weighted: Keys with a light spring plus a small weight, but no hammer mechanism. Heavier than a synth, much lighter than a true piano. Common on arrangers and entry workstations, but not ideal for classical practice.
Escapement (let-off): A subtle notch you feel partway down a grand piano's key travel, from the hammer disengaging. Premium digital actions simulate this for a more authentic touch — useful mostly for classical repertoire.
Ivory / ebony feel: A fine-textured key surface that absorbs moisture from fingers and improves grip, imitating real ivory and ebony keytops used on vintage pianos.
Touch sensitivity (velocity): How the piano responds to how hard or softly you strike a key — louder when you hit harder, softer when you play gently. Usually adjustable between a few presets.
Triple-sensor detection: Three sensors along a key's travel detect finer gradations of motion, especially during fast repeated notes. Higher-end actions use this; two-sensor systems are common on entry pianos.
88 / 76 / 61 / 49 keys: 88 keys covers the full acoustic piano range and is the standard for serious practice. 76 covers most popular and classical repertoire. 61 is the keyboard standard. 49 is mini-key territory, suitable for beginners and compact setups only.

Sound & Voicing

Polyphony: The maximum number of notes the piano can produce at once — including held notes and decaying reverb tails. 128 is enough for most players; 192-256 is common on higher-end models.
PCM sampling: Real recordings of acoustic notes stored in the piano and played back on each keystroke. The most common sound-generation method. Sample quality and quantity vary widely.
Sound modeling (physical modeling): The piano calculates each note's sound in real time from a mathematical model of a real instrument rather than replaying samples. More dynamically responsive, used by Roland SuperNATURAL, Kawai Harmonic Imaging XL and similar engines.
String resonance: Simulation of how strings on an acoustic piano vibrate sympathetically with the notes you play. Adds a sense of depth and realism. Usually adjustable from off to strong.
Damper resonance: The wash of open-string resonance you hear on an acoustic piano when the sustain pedal is pressed. Quality implementations make a clear difference; cheap ones are subtle.
Key-off samples: The faint noise of a damper returning to the string when you release a key. Found on higher-end pianos; contributes to a natural, finished sound.
Reverb: Adds a sense of space — room, hall, cathedral. Most pianos offer several types with adjustable depth.
Chorus: Layers slightly detuned copies of a sound to thicken it. Common on electric piano, strings, and pad voices; rarely used on acoustic piano sounds.

Pedals

Sustain pedal (damper pedal): The rightmost pedal. Holds notes after you release the keys by lifting the simulated dampers. The one pedal every piano needs.
Soft pedal (una corda): The leftmost pedal on a three-pedal unit. Softens the tone, simulating an acoustic grand's shifted hammer. Required for some classical repertoire.
Sostenuto pedal: The middle pedal. Sustains only notes being held when the pedal is pressed — useful for holding a bass note while playing melody lines above. Less common in digital pianos.
Half pedaling: Partial depression of the sustain pedal for gradations of damper control. Only works with continuous (pressure-sensing) pedals, not simple on/off switches.
Continuous pedal: A sustain pedal that senses how far it's pressed down, enabling half-pedaling. The better pedals included with mid-range and up digital pianos are continuous.

Connectivity

USB MIDI: A USB cable carries MIDI data between the piano and a computer or tablet. Used for learning apps, notation software, and DAWs. Universally supported, zero latency issues.
Bluetooth MIDI: Wireless MIDI to a phone or tablet for apps like Flowkey, Simply Piano, or GarageBand. Convenient; slightly higher latency than USB but usually imperceptible.
Bluetooth Audio: Streams audio from your phone through the piano's speakers — play along with songs, follow YouTube tutorials. Different feature from Bluetooth MIDI; pianos often have one but not the other.
Line out: Stereo (or mono) output jacks to send the piano's signal to a mixer, amplifier, audio interface, or recording setup. Essential for stage and studio use.
Aux in (audio input): Stereo input to mix external audio (phone, tablet, backing track) with the piano's sound through its own speakers. Handy for practice with recordings.

Features & Performance

Dual / Layer mode: Plays two sounds at once across the whole keyboard — classic piano + strings, for example. Great for ballads; uses more polyphony.
Split mode: Assigns different sounds to the lower and upper halves of the keyboard — bass on the left, piano on the right, for instance. The split point is usually adjustable.
Duo / Duet mode: Divides the keyboard into two identical ranges at the same octave so a teacher and student can play the same part side-by-side. A great feature for lessons at home.
Transpose: Shifts the pitch of the whole keyboard up or down in semitone steps — play in one key while the instrument sounds in another. Useful for accompanying singers.
Metronome: Built-in timing click that helps you practice at a steady tempo. Adjustable BPM and time signature on most models.
Lesson function: Preset songs split into left and right hand parts, with the option to mute one hand and play along. Yamaha and Casio models are particularly strong here.
Recording: Captures what you play as MIDI data (sometimes audio too). Lets you review your practice or layer multiple parts. Track counts range from 1 to 16 depending on model.
MSRP vs. street price: MSRP is the manufacturer's listed retail price. The street price — what retailers actually charge — is often 10–30% lower. Compare both when budgeting.

Keep learning

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